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Since the early 1990s, Bugatti owned the quad-turbo conversation. From the EB110 V12 to the massive W16 in the Veyron and Chiron, four turbochargers became the brand’s signature. But as of April 26, 2026, that unique claim is fading. BMW produces the B57 quad-turbo diesel, a sophisticated four-turbo unit available across several models, while Bugatti itself has moved to a hybrid V16 without turbochargers. So who makes quad-turbo engines besides Bugatti? Here’s the full picture.
Bugatti’s quad-turbo story begins with the EB110, the V12-powered supercar launched in 1991. Its 3.5-liter engine used four small turbochargers to produce around 560 hp in standard trim, while later Super Sport versions reached 610 hp. The layout was unusual: a high-revving V12 paired with four turbos to sharpen throttle response and cut lag.
After Volkswagen took over Bugatti, the W16 became the new quad-turbo flagship. The Veyron, launched in 2005, used an 8.0-liter W16 with 16 cylinders arranged in a wide W configuration and four turbochargers to deliver more than 1,000 horsepower. Every major Veyron and Chiron variant kept the same architecture, with output climbing beyond 1,500 hp in the Chiron Super Sport.
That run made Bugatti synonymous with quad-turbo engineering. For over three decades, anyone looking for a factory four-turbo engine was almost certainly talking about a Bugatti.
BMW broke that pattern with a completely different approach. Instead of building a gasoline hypercar engine, BMW chose a diesel inline-six. The B57D30, introduced in the 2016 M550d xDrive and later used in the X5 M50d, X6 M50d, and 750d, uses four turbochargers in a two-stage arrangement. It produces 400 hp and 760 Nm of torque.
A diesel with four turbos? Yes. BMW split the six cylinders into two groups, each group feeding two turbochargers in series. A smaller high-pressure turbo spools quickly for low-speed response; a larger low-pressure turbo takes over at higher engine speeds. With two groups and two stages, the system uses four total turbochargers to build boost smoothly without relying on one giant turbo.
The BMW design stands on its own merits. It combines diesel efficiency with strong mid-range punch. The M550d can reach 60 mph in around four and a half seconds while still returning surprisingly good highway fuel economy. It isn’t a Bugatti rival in speed, but it is a genuine factory quad-turbo engine.
The term can be slippery. A turbocharged engine uses exhaust gases to spin a turbine, which forces more air into the cylinders. One turbo is single-turbo; two are twin-turbo; three are tri-turbo; four are quad-turbo.
But multiple turbos can be arranged in different ways. They can run in parallel, each bank of cylinders feeding one or more turbos. They can also run in series, where a small turbo feeds the intake of a larger turbo or vice versa. BMW’s B57 uses a combination of series and parallel setups to optimize torque across the rev range.
The Bugatti W16 is different. Its four turbochargers are mounted to handle the enormous airflow of a 16-cylinder engine. That engine does not need the same staged arrangement, because the W16 has enough cylinder volume to spool larger turbos quickly. Two very different engineering solutions, same headline figure: four turbos.
Four turbochargers sound exciting, but most automakers avoid the layout for good reasons.
Cost is the first barrier. Four turbochargers mean more parts, more plumbing, more heat shielding, and more calibration work. A production car must survive years of stop-and-go driving, hot climates, cold starts, and owner abuse. Turbos are expensive to replace, and quad-turbo complexity multiplies the risk.
Packaging is another issue. On a V engine, two turbos often fit neatly inside the V or around the outer exhaust banks. On a straight-six, fitting four turbos requires clever exhaust routing to balance cylinder groups. BMW had to develop advanced thermal management to keep all four units within a safe temperature range.
Performance trade-offs also matter. Turbos create exhaust backpressure, which can reduce high-rpm efficiency. A quad-turbo system must be tuned carefully so that total power and response justify the added weight and friction. This is why many automakers settle for one big turbo or two well-placed turbos.
Still, a quad-turbo system can be an elegant solution when engineers want both low-rpm response and high-end power. Bugatti did it for hypercar performance; BMW did it for diesel torque and clean response in a heavy luxury SUV or sedan.
When you search for quad-turbo engines beyond Bugatti, you will find aftermarket shops and race engineers who have built four-turbo monsters. Some have been built for drag racing, hill climbs, and dyno showpieces. These are not production engines, and they rarely need to meet emissions, cold-start, or warranty requirements.
There are also commercial and industrial engines with multiple turbochargers, but they belong to trucks, ships, and generators. Those units follow different cost and duty-cycle rules. For the road-car world, BMW and Bugatti are the only names with credible factory quad-turbo production engines.
Some supercar rivals, such as Koenigsegg and Hennessey, use twin-turbo V8s. Mercedes-AMG has built powerful twin-turbo V8s and V12s, but never offered a factory quad-turbo passenger engine. This makes BMW’s achievement more unusual: a volume-brand diesel with four turbos, not just a one-off supercar.
The biggest recent change is that Bugatti is leaving quad-turbo power behind. In 2024, Bugatti revealed the Tourbillon, the successor to the Chiron. It drops the W16 entirely, using a naturally aspirated 8.3-liter V16 developed with Cosworth, plus a plug-in hybrid system. The V16 is larger and makes more combined output than the W16, but it has no turbochargers.
That means the W16 quad-turbo era is effectively over for new Bugatti models. The Chiron-based Super Sport, Centodieci, and Mistral are among the final vehicles with the famous four-turbo W16. The Tourbillon signals a shift toward electrification, where turbo lag matters less because electric motors fill the gaps.
This creates a strange moment in 2026. The company that defined the quad-turbo engine no longer builds a new quad-turbo powertrain. Meanwhile, BMW’s B57 diesel continues to hold the flag for four-turbo production cars.
The quad-turbo niche is unlikely to grow. Automakers are moving toward hybrid turbo engines, electric supercars, and downsized forced-induction units. Four turbos add complexity to an already crowded engine bay, especially as thermal and emissions regulations tighten.
But the engineering lessons will survive. BMW’s two-stage turbocharging has influenced later diesel and gasoline designs. The idea of using multiple small turbos to reduce lag has spread through the industry, even if most brands stop at two.
For enthusiasts, a quad-turbo engine remains a stamp of extreme engineering intent: Bugatti did it for outrageous performance, BMW did it for diesel efficiency and responsiveness. When someone asks who makes quad-turbo engines besides Bugatti, the best answer for production cars is BMW.
That may feel odd because the two brands are so different, but the evidence sits under the hood of the B57 diesel. BMW built a four-turbo engine that works in every commuter condition, proving that quad-turbo is not just a Bugatti fantasy. And with Bugatti turning naturally aspirated, BMW is now the most accessible route to a factory quad-turbo car.
